SPRING. 



bojrgy and other wet land, which ie moltly caufed in a 

 different w^y than by that of fprings, but which, as par- 

 taking in feme degree of the natare of that kind of bogs, 

 and being capable of having the wetnefs removed by fuch 

 means as are had recourfe to in fpring-draining, may be 

 confidered in this place without impropriety. In many 

 part* of the kingdom there are confiderable trafts of land 

 which lie walte and uncultivated, owing to wetnefs in 

 a particular Ctuation, that might, by means of letting down 

 the waters into a porous under-ttratum, be eafily drained, 

 and rendered much more produftive. The caufe of their 

 wetnefs proceeds not from fprings lying under the furface, 

 nor from the overflowings of any of the adjoining higher 

 grounds, but from the accumulation of rain-water llag- 

 nating on a retentive body of clay, or other impervious 

 fubftance, through which the- water can have no defcent ; 

 and being alfo furrounded with higher ground of the fame 

 impervious nature, the water of itfelf can have no natural 

 outlet. Such ground, when it becomes boggy, is commonly 

 culled lanJ-Iocied hogs. The fituation of thefe bogs being 

 often fo much lower than the grounds that furrour.d them, 

 the cutting of a main drain, or conduftor, through the 

 bank, for carrying off the water coUefted by the fmaller 

 drains, would, in many cafes, be attended with an expence 

 greater than the value of fuch land when drained. The thick- 

 nefs of the impervious itratum that retains and upholds the 

 water is often fo great, that although the ilrata under it 

 be of a porous and open nature, as rock-fand or gravel, the 

 water can find no paflage whereby of itfelf to defcend 

 through the one into the other ; and, therefore, by its long 

 ftagnation above, all the coarfe vetegables that have, for 

 a feries of years, been produced on its furface, and even the 

 upper part of the foil itfelf, are formed into a body of 

 peat-earth, equally foft and lefs produftive than that of any 

 fpring-bog, and which is only paffable by cattle in very 

 dry feafons, when the wind and fun exhale part of iti 

 moifture ; and is even then inaccefhble to the plough. 

 The drainage of thefe bogs mull be effefted in a manner 

 different from that of thofe above, or fpring-bogj, the caufe 

 of both not being the fame in their nature, as already feen. 

 It may probably be done in the following maimer at the 

 leaft expence. The firft drain mull be made in the middle 

 or lowefl part of the ground, and into this all the others 

 mull lead. The number and direftion of thefe mull de- 

 pend on its extent. They mull be cut through the peat, 

 or wet, fpongy, upper foil, to the top of the clay or reten- 

 tive fnb-(lratum, which mull be perforated by the auger, in 

 order to give an outlet downwards for the water, which will 

 be abforbed by the porous Ilrata below. The making one 

 large pit or well in the middle or lower part of the bog, 

 dug through into the porous fubllrata, with the drains 

 leading into it, would anfwer equally well, and would fave 

 boring along each of the drains : this is a method which has 

 frequently been pradlifed with fuccefs in different dillridls. 

 In Hertfordlhire, according to the correfted account of 

 the agriculture of that ditlrift, if a pit be funk twenty or 

 thirty feet in depth, in the middle of a held, through the 

 red, flinty, and imperviou', clay of the county, into the 

 chalk below, when the ufual quantity of chalk is taken out, 

 the pit-fhaft is filled up with the flints which are coUedled 

 out of the chalk and clay, and the top, or furface-drainage, 

 of this part of the held, much fliortened for ever afterwards, 

 by making principal drains from the part of the field above 

 the level of the lop of the pit terminate therein, and the 

 fuperabundant moilture will efcape through the flints in the 

 pit-lhaft to the chalk below. And if a drain be carried into 

 a limeilone quarry, it is feldora necelfary to carry it farther. 



In dells or -hollows of confiderable extent, which arc 

 covered with an impervious ftratum, and from which there 

 is no natural drainage ; fuch, for inftance, as the valley 

 between Mold, the fhire-town of Flintlhire, and the adjoin, 

 ing high land j a pit about f )ur feet in diameter, and fifteen 

 feet in depth, more or lefs, as the cafe may require, is funk 

 through the impervious fuper-llratum into a pervious 

 ftratum of gravel, and the rain-water, and that of fome 

 adjoining (prings, are carried from the furface thereby : the 

 pit is railed round to prevent cattle from falling into it. 

 It is here remarked, that though in this, as well as in many 

 other inllances that might be given, the top-water efcaped 

 through the pervious fub-ftratum, the effeft might have 

 been direftly the contrary. It is, coiifequently, advifed, 

 that the impervious fuper-llratum, in all fuch caf^a, fhould 

 fii'l be perforated by bore-rods, as the holes made by them 

 are eafily Hopped up. 



Where the firll method is had recourfe to, the drains 

 fliould be cut as narrow as poflible, and, after the auger- 

 holes have been made, fhould be filled with loofe flones to 

 within a foot and a half of the furface ; and this vacuity may 

 be filled up with part of the earth taken out, having a turf, 

 grafs-fide downwards, next the Hones. The water and 

 noxious moillure, contained in the peat or upper foil, will 

 be extraitled by the drains, and will fubfide through the 

 auger-holes into the porous ilrata below. If the ground is 

 afterwards ploughed, care mutt be taken in forming the 

 ridges, and giving them a proper defcent towards the main 

 drain, which will greatly affill the others in difcharging any 

 heavy falls of rain-water. 



Before proceeding to drain this kind of land in the man- 

 ner delcribed, the following obfervation mud be attended 

 to. It fhould be difcovered, in the firll place, whether the 

 porous flrata immediately under the clay be dry, and will 

 receive the water, when let down into it from above ; or, 

 being faturated with water itfelf, may, in place of receiving 

 more, throw up a greater quantity to the furface ; and 

 thus, inftead of remedying the evil, render it worfe. This 

 may fometimes be the cafe ; and the fubllrata may contain 

 water that makes no appearance on the furface, at this place, 

 owing to the fuperincumbent body of clay, but which, 

 being connefted with fome higher fpring, may flow up, 

 when a vent is given to it by the auger. Thus would a 

 greater quantity of water be brought to the furface, which, 

 having no outlet through the circumjacent bank, would 

 render the ground much more wet, and might even, in fome 

 fituations, almofl form a lake. If the furrounding high 

 ground declines deeper or lower than the bog, although at 

 fome ditlance, by means of a fpirit-level, and the appearance 

 of the furface, the nature of the under-ltrata may in a cer- 

 tain meafure be difcovered ; and although it fhould already 

 contain water, a drain may be there cut to draw off that 

 water, and alfo what is let down into it from above. 



It not unfrequently happens, that fprings, or Jpouts, as 

 they are commonly termed, rife in the middle of a field, or 

 portion of ground at a diltance from any ditch or open 

 drain, into which the water may be difcharged ; fo that a 

 covered drain, brought from the nearell outlet, would pafs 

 fo far through dry ground, as to render the expence of con- 

 ducting the water from the fpouty part greater than the 

 injury done by it. In order to remedy this evil, it is ne- 

 celfary to begin by cutting a drain a few yards in length, or 

 by finking a pit into the porous foil immediately between 

 the lower fide of the wet and next dry ground ; and from 

 that to bring up an upright drain to the upper fide of tke 

 wet ground, from which a branch mull be taken to both 

 fides, along the upper fide of the wet, fo £sr as it goesv 



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